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101.
Eremina EIu Bondarenko VM Zvereva SI Nikitina OI Shaposhnikova LI 《Zhurnal mikrobiologii, epidemiologii, i immunobiologii》2008,(3):62-66
Forty-eight patients with duodenal peptic ulcer disease infected with Helicobacter pylori were examined. All patients undergo conventional 1-week eradication therapy. After its ending the patients were randomized to two groups: those who will be treated by synbiotics or control group. Normoflorin B and Normoflorin L, which contain bifidobacteria or lactobacilli in complex with different microelements, vitamins, aminoacids, organic acids, and antioxidants, were used as synbiotics. Morphologic study of biopsy samples of small intestine mucosa were performed in patients from both groups. It was determined that eradication therapy worsened existing symptoms of dyspepsia in 80.9% of cases or lead to their emergence, connected with dysbiotic manifestations, in 55.5% of patients. Inclusion of synbiotics in complex therapy resulted in rapid and effective elimination of dyspeptic symptoms, promoted recovery of affected morphologic and functional states of small intestine mucosal epithelium, and optimized metabolic processes important for the digestion. 相似文献
102.
Kostinov MP Pakhomov DV Snegova NF Nikitina TN Zinkina TN 《Zhurnal mikrobiologii, epidemiologii, i immunobiologii》2008,(4):50-55
Course of postvaccinal period after injection of vaccine against Haemophilus influenzae type b administered simultaneously with vaccines of Russian national immunization schedule was studied in children born from HIV-infected mothers. Good tolerability of the vaccine administered concomitantly with diphtheria-tetanus-whole cell pertussis and inactivated polio vaccines (Imovax Polio), which is comparable with tolerability in healthy children, was demonstrated. Prevaccination titers of antibodies and their dynamics during immunization process were described. Increase of levels of antibodies was detected both in the group of children with perinatal contact with HIV infection and in the group of HIV-infected children. 相似文献
103.
Vetchinkina EP Nikitina VE Tsivileva OM Garibova LV 《Prikladnaia biokhimiia i mikrobiologiia》2008,44(1):76-83
We studied changes of the hemagglutinating activity of intracellular lectins of the basidiomycete Lentinus edodes (shiitake) at various stages of its morphogenetic development depending on erythrocyte type, growth medium, and lectin purification degree. Under certain experimental conditions, the specific lectin activity at the brown mycelium film stage exceeded the corresponding value for nonpigmented mycelium. The sensitivity of the lectins towards trypsin-treated rabbit erythrocytes was no less than a hundredfold higher than towards any other erythrocyte type studied. The general regularities of specific activity change did not depend on nutrient medium composition. With purification of intracellular shiitake lectins, their sensitivity to human erythrocytes decreased seventyfold or more, whereas their sensitivity to rabbit erythrocytes increased by the same factor. 相似文献
104.
105.
The dentition and tooth crown microstructure of gekkonids and eublepharids are examined. Scanning electron microscopy shows that the lingual surface of teeth in these lizards has one, two, or, occasionally, several cusps separated by grooves. The teeth of geckoes usually have two (lingual and labial) cusps in the apical region. With respect to the number of teeth, the majority of Gekkota fall into two groups. The first includes a few species with many teeth (50 or more) in the dentary and maxilla, the eublepharids Goniurosaurus and Aeluroscalabotes, and the gekkonid Cyrtopodion louisiadensis. The second group, comprising most of the species, is subdivided into two subgroups, species with 20–30 or 30–40 teeth in jaw bones. Teratoscincus belongs to the first subgroup of the second group. 相似文献
106.
GUY WOODWARD JOHN B. DYBKJÆR JÓN S. ÓLAFSSON GÍSLI M. GÍSLASON ELÍSABET R. HANNESDÓTTIR NIKOLAI FRIBERG 《Global Change Biology》2010,16(7):1979-1991
The Earth is experiencing historically unprecedented rates of warming, with surface temperatures projected to increase by 3–5 °C globally, and up to 7.5 °C in high latitudes, within the next century. Knowledge of how this will affect biological systems is still largely restricted to the lower levels of organization (e.g. species range shifts), rather than at the community, food web or ecosystem level, where responses cannot be predicted from studying single species in isolation. Further, many correlational studies are confounded with time and/or space, whereas experiments have been mostly confined to laboratory microcosms that cannot capture the true complexity of natural ecosystems. We used a ‘natural experiment’ in an attempt to circumvent these shortcomings, by characterizing community structure and trophic interactions in 15 geothermal Icelandic streams ranging in temperature from 5 °C to 45 °C. Even modest temperature increases had dramatic effects across multiple levels of organization, from changes in the mean body size of the top predators, to unimodal responses of species populations, turnover in community composition, and lengthening of food chains. Our results reveal that the rates of warming predicted for the next century have serious implications for the structure and functioning of these fragile ‘sentinel’ ecosystems across multiple levels of organization. 相似文献
107.
E. A. Sazhenova T. V. Nikitina N. A. Skryabin L. I. Minaycheva T. V. Ivanova T. N. Nemtseva S. Yu. Yuriev I. D. Evtushenko I. N. Lebedev 《Russian Journal of Genetics》2017,53(3):376-387
An analysis of differential methylation of 47 imprinted genes in placenta tissues of spontaneous abortions at the first trimester of pregnancy from women with recurrent pregnancy loss or with one sporadic abortion was performed using the DNA-microarray approach. We showed that epimutations of the imprinted genes were registered significantly more often in abortions from women with recurrent miscarriage in contrast to the embryos from women with sporadic pregnancy loss with frequency of 6.2 and 3.7% per locus, respectively (p < 0.01). The predominant type of epimutation appeared to be a postzygotic hypomethylation of the imprinted genes on chromosomes of maternal origin, which was observed in the examined samples in 5.1 and 2.89% of cases, respectively. Replicative study of the methylation status of seven imprinted genes (DLK1, PEG10, PLAGL1, KCNQ1OT1, PEG3, GRB10, and PEG1/MEST) in the enlarged embryo samples supported the results of microarray analysis in respect to both epimutation frequency and predominance of somatic hypomethylation of maternal alleles. It was also demonstrated that pregnancy loss was associated with multilocus methylation defects of imprinted genes, the frequency of which was also significantly increased in the placental tissues of spontaneous abortions in women with recurrent miscarriage. 相似文献
108.
Anna V. Tugarova Elena P. Vetchinkina Ekaterina A. Loshchinina Andrei M. Burov Valentina E. Nikitina Alexander A. Kamnev 《Microbial ecology》2014,68(3):495-503
The ability to reduce selenite (SeO3 2?) ions with the formation of selenium nanoparticles was demonstrated in Azospirillum brasilense for the first time. The influence of selenite ions on the growth of A. brasilense Sp7 and Sp245, two widely studied wild-type strains, was investigated. Growth of cultures on both liquid and solid (2 % agar) media in the presence of SeO3 2? was found to be accompanied by the appearance of the typical red colouration. By means of transmission electron microscopy (TEM), electron energy loss spectroscopy (EELS) and X-ray fluorescence analysis (XFA), intracellular accumulation of elementary selenium in the form of nanoparticles (50 to 400 nm in diameter) was demonstrated for both strains. The proposed mechanism of selenite-to-selenium (0) reduction could involve SeO3 2? in the denitrification process, which has been well studied in azospirilla, rather than a selenite detoxification strategy. The results obtained point to the possibility of using Azospirillum strains as endophytic or rhizospheric bacteria to assist phytoremediation of, and cereal cultivation on, selenium-contaminated soils. The ability of A. brasilense to synthesise selenium nanoparticles may be of interest to nanobiotechnology for “green synthesis” of bioavailable amorphous red selenium nanostructures. 相似文献
109.
R. Campos‐Herrera E.G. Johnson F.E. EL‐Borai R.J. Stuart J.H. Graham L.W. Duncan 《The Annals of applied biology》2011,158(1):55-68
Quantitative real‐time PCR (qPCR) techniques are being increasingly used to provide accurate and reliable methods to identify and quantify cryptic organisms in soil ecology. Entomopathogenic nematode (EPN) diversity in Florida is known to be extensive and our phylogenetic studies of the D2D3 and ITS regions showed the occurrence of an additional species‐complex in the Steinernema glaseri‐ group in widely separated locations of the peninsula. To address ecological studies, we developed and used qPCR assays to detect and quantify six species of EPN that are naturally distributed in Florida citrus orchards (Steinernema diaprepesi, Steinernema riobrave, Heterorhabditis indica, Heterorhabditis zealandica, Heterorhabditis floridensis and an undescribed species in the S. glaseri group) and an exotic species, S. glaseri. Species‐specific primers and TaqMan® probes were designed from the ITS rDNA region. No nonspecific amplification was observed in conventional or qPCR when the primers and probes were tested using several populations of each of the Florida species and other exotic EPN species. Standard curves were established using DNA from pure cultures. We optimised a protocol for extracting nematodes and DNA from soil samples that can detect one EPN added to nematode communities recovered by conventional extraction protocols. A survey of an 8‐ha orchard in April 2009 compared the EPN spatial patterns derived from qPCR to that obtained by baiting soil samples with Galleria mellonella larvae. The patterns were also compared to those derived from the same site in 2000–01 by repeatedly (12 sampling events) baiting soil in situ with caged larvae of the root weevil Diaprepes abbreviatus. The qPCR assay was more efficient than the Galleria baiting method for detecting the EPN species composition in population mixtures. Moreover, the spatial patterns of EPN in this orchard were remarkably stable over the course of nearly a decade. The pattern of H. zealandica detected at the site 8 years earlier was related to those derived by qPCR (P = 0.002) and from sample baiting (P = 0.02). The spatial pattern of H. indica derived from qPCR, but not that from sample baiting, was also related to the earlier pattern (P = 0.01). The qPCR assay developed here is a fast, affordable and accurate method to detect and quantify these EPN species in soil and offers great potential for studying the ecology of EPN. 相似文献
110.
The interaction was investigated between the haloalkaliphilic nonsulfur purple bacteria Rhodovulum steppense A-20sT and layered aluminosilicates: micas (biotite, phlogopite, and muscovite) and clay minerals (montmorillonite and kaolinite).
The interaction between all components of this system (minerals, water, medium, and bacteria) resulted in the changes in the
chemical composition of the minerals and solutions. These changes were especially significant in the presence of bacteria.
By using some elements for growth and promoting their transfer into the exchange pool of the minerals, bacteria removed these
elements from the medium. The content of exchange bases in the aluminosilicates incubated in the presence of bacteria was
several times higher than in the minerals incubated in sterile medium. The observed saturation of the mineral phase with potassium
and magnesium may be considered the initial phase of diagenesis of the aluminosilicates under study. 相似文献